Based on literature review and malacological collections, 168 native freshwater bivalve and five invasive species have been recorded for 52 hydrographic regions in South America. The higher species richness has been detected in the South Atlantic, Uruguay, Paraguay, and Amazon Brazilian hydrographic regions. Presence or absence data were analysed by Principal Coordinate for Phylogeny-Weighted. The lineage Veneroida was more representative in hydrographic regions that are poorer in species and located West of South America. The Mycetopodidae and Hyriidae lineages were predominant in regions that are richest in species toward the East of the continent. The distribution of invasive species Limnoperna fortunei is not related to species richness in different hydrographic regions there. The species richness and its distribution patterns are closely associated with the geological history of the continent. The hydrographic regions present distinct phylogenetic and species composition regardless of the level of richness. Therefore, not only should the richness be considered to be a criterion for prioritizing areas for conservation, but also the phylogenetic diversity of communities engaged in services and functional aspects relevant to ecosystem maintenance.

The influence of the glass transition temperature and the mechanical and anticorrosion properties of factors such as the amount of plasticizer added to an epoxy primer were investigated by DSC (differential scanning calorimeter), DMA (dynamic mechanical analysis), stress-strain tests, salt fog spray tests, accelerated tests, and electrochemical tests.The addition of plasticizer results in a decrease in the glass transition temperature and a change in the mechanical properties. Different tests were carried out to the optimum percentage of plasticizer content (1.5-3% weight ratio to epoxy resin) required to obtain the maximum anticorrosion performance of the epoxy primer. These changes are explained by the structural-kinetic effect exerted by the plasticizer on the chemical crosslinking in the course of the epoxy network synthesis and the increase in the excess free volume.

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